When do you charge your electric golf cart?

When it either runs out of battery or when it is nearly dead! :L

Best rule of thumb is to recharge when the batteries are at about 60% capacity. You should not recharge every time you run down the street to the store, operating for 5 minutes. If you have a cumulative running time of about 20 minutes, then you should recharge. Battery packs have about 1000 charge cycles. That is their life span. A fleet car used and charged every day = 3 1/2 years. I have seen batteries, well cared for and charged sparingly, last 10 years.